Aeronautical propeller



Nov. 17, 1931. A. F. EUcHENHor-'ER AERONAUTICAL PROPELLER Filed April29. 1929 2 Sheets-Sheet 2 Patented Nov. 17, 1931 PAT-ENT OFFICE ADOLPHF. EUCHENHOFEB, F DAYTON, OHIO AERNAUTICAL PBOPELLEB Application ledApril 29, 1929. Serial No. 358,843.

This invention relates to an aeronauticalpropeller and more particularlyto the propeller hub and the means for mounting the blade therein. 6 Oneobject of the present invention is to provide la propeller of suchacharacter that the blade may be quickly and easily mounted in the hubsocket, adjusted with relation thereto and rigidly secured in itsadjusted .1Q position. y

A further object of the invention is to pro: 'vide a propeller in whichthe blade may be adjusted longitudinally with Irelation to the hubstructure Without modifyingthe pitch angle thereof. l

A further object of the invention is to provide such a propeller whichwill be simple in its construction, of a strong durable character andwhich may be produced at av relatively low cost. v

Other objects of the invention will appear as the-device is described.In the accompanying drawings Fig. 1 is a front elevation 'of apropeller, with the outer portion of the blades broken away, and withthe hub structure partly in section; Fig. 2 is a plan view of the hubstructure partly in section and with the blades broken away; Fig. 3 isan end elevationof the hub structure with the propeller blade insection; Fig. 4 is a transverse section taken on the line 4 4. of Fig.1; Fig.l 5 is a. transverse section taken on the line 5 5 of Fig. 1; andFig. 6 is a detailv view of the connecting member.

In these drawings I have illustrated one embodiment of my invention 'andhave shown the sameyas comprising a hub structure 1l) having atransversev central opening to receive the propeller shaft. The hub maybe mounted on the propeller shaft in any suitable manner. In the presentinstance a hub supporting structure or tapered sleeve 11 is mounted onand rigidly secured to the end Aot the shaft, a portion of which isshown at 12, and this'sleeve has a circumferential iange 13 adapted tobe engaged by a corresponding flange 14 on the hub structure when thelatter is mounted on the sleeve, as shown in Fig. 2. The two flanges maybe rigidly connected one to the other in any suitablemanner, as by meansof bolts 15. The hub structure has at each end thereof a blade receivingsocket 16. The two sockets and the means for securing the blades thereinare identical and the de scription of one will apply to both. V

The socket 16 preferably has a smooth cy- 55 lindrical inner surfacev atthat end adjacent to the axis of the hub, asshown at 17, and the shankof the blade 18 has an inner end portion 19 shaped to lit snugly Withinthe 60 cylindrical portion of the hub socket but capable of bothrotatory and axial adjustment therein. The' means for securing the bladein the socket is such as to permit the adjustment of the blade bothabout a longitudinal axis, to establish the correct pitch angle, and inthe direction of its length to enable it to be properly positioned withrelation to v the other blade so as to balance the propeller.

To accomplish this I have mounted on the 7o shank of the blade, on theouter side of the end-portion 19 thereof, a connecting member which isheld 'against movement lengthwise ofthe blade but Within which the blademay be rotated. This connecting member extends into vthe outer portionof the socket and is so mounted therein that it may be adjustedlengthwise of the socket, thus imparting lengthwise adjustment to theblade. Means are provided for rigidly securing the con- 30 lnectingmember in its adjusted position within the socket and for rigidly secur`the same to the blade. These parts of the evice may take various formsbut, in the preferred construction, the shank of the blade is prog5vided with a circumferential groove 20 inwhich is mounted a split collar21 of such Va length that its ends will abut against the end. walls ofthe groove and thus hold the collar against axial movement with4relation 90 to the blade. The exterior surface of the collar isthreaded and the outer end portion of the socket is provided 4withinternal threads to receive the same so that by rotating .the collarwith relation to the blade the blade may be caused to move lengthwise ofthe socket. Preferably the collar is provided at its outer end withavlange or a head 22 to facilitate its adjustment. The outer end orthreaded portion of the socket is also-split,

preferably at a plurality of points, as shown at 23, and a clampingdevice, such as a split rin 24, extends about the split end of the socet for clamping the same tightly about the collar and for clamping thecollar tightly about the shank of the blade. The clamping ring has theusual apertured lugs 25 through which extends a bolt 26a by lmeans ofwhich the ring may be tightenedabout the socket. It is desirable thatthe ring should be retained in a fixed circumferential position withrelation to the socket and I have here shown the same as having aninwardly extending projection, such as a pin 26, which enters a recess27 in the outer surface of the socket and holds the ring againstmovement circumferentially of the socket. The recess 27 may, if desired,be elongated in a direction of the length of the socket but this is notnecessary as it is immaterial whether or not the clamping ring contactswit-h the flange on the split collar. It will be apparent that when theclamping ring is loosened the split collar or connecting member may berotated to adjust the blade in the direction of its length and that theblade may be rotated about its longitudinal axis to establish thecorrect pitch angle, or it may be held against rotation and thelongitudinal adjustment of the blade effected without dis. turbing thepitch angle thereof. When the desired adjustments have been effected'the clamping ring is tightened down and the parts thus rigidly securedin their adjusted positions.

To facilitate the mounting of the split collar in the groove in the hubI prefer to make the same in two substantially semicylindrical parts andafter the two parts have been placed in position within the groove inthe shank of the blade they are welded one to the other, at one side ofthe collar, so as -to produce in effect a one piece collar. To this endI have shown the collar .tion of the blade shank has on its outerperiphery a circumferentially arranged series of graduations 31 and theadjacent portion of the socket has a sight opening 32 through which thegraduations are visible. Preferably the socket is provided-with a fixedmark or indicator to cooperatef with the graduationson the blade shank.As here shown, the wall ofthe sight opening is flared and this ared wallis provided with a line or mark 33 which may register with any -one ofthe graduations.

While I have shown and described one embodiment of my invention I wishit to be understood that I do not desire to be limited to the detailsthereof as various modifications may occur to a person skilled in theart.

Having now fully described my invention, what I claim as new and desireto secure by Letters Patent, is:

1. In a propeller, a hub having a socket and a blade having a shankextending into saidsocket, a connecting member extending about saidshank, mounted in said socket for adjustment lengthwise thereof and heldagainst lengthwise movement withA relation to said shank during saidadjustment, and means for rigidly securing said connecting member inadjusted positions in said socket and for holding said connecting memberand said shank against relative rotatory movement.

2. In a propeller, a hub having a socket and a blade having a shankextending into said socket, a split collar mounted on said shank, heldagainst movement lengthwise thereof and mounted in said socket foradjustment lengthwise thereof, and means for rigidly securing saidcollar in adjusted positions in said socket and for clamping the sametightly about said shank.

3. In a propeller, a hub having a socket and a blade having. a shankextending into said socket, a split collar mounted on said shank, heldagainst movement lengthwise thereof and having screw threaded connectionwith said socket, and means for rigidly securing said collar in adjustedpositions in said socket and for clamping the same tightly about saidshank.

4. In a propeller, a hub provided with a socket having its outer endportion split, a blade having a shank extending into said socket, asplit collar mounted on said shank, held against movement lengthwisethereof and mounted in said outer end portion of saidsocket foradjustment lengthwise thereof, and means for clamping the split end ofsaid socket about said collar and for clamping said collar about saidshank.

5. In a propeller, a hub provided with a socket having its outer endportion split and having an internal screw thread, a blade having ashank extending into said socket, a split collar mounted on said shankfor adj ustment about the axis thereof, heldagainst movement lengthwisethereof and having an external thread to engage the internal thread ofsaid socket,'and means for clamping the split end of said socket aboutsaid collar and for clamping said collar about said shank.

6. In a propeller, a hub provided with a socket having its outer endportion split and having an internal screw thread, a blade fittingsnugly 'but adjustably in the innermovement lengthwise thereof andhaving an external thread to engage the internal thread of said socket,a clamping ring mounted about the split end portion of said socket andheld lagainst circumferential movement with relation thereto.

7. In a propeller, a hub provided with a socket having its outer endportion split and having an internal screw thread, a blade having ashank extending into said socket and provided with a circumferentialgroove, a split collar mounted in said groove and having a screw threadto engage the thread in said socket, and means for clamping the splitend of said socket about said collar and for clamping said collar aboutsaid shank.

8. In a propeller, a hub provided with a socket having its outer endportion split and having an internal screw thread, a blade having ashank extending into said socket and provided with a circumferentialgroove, a split collar mounted in said groove and conlprising separateparts to be connected one to the other at one side of said collar afterthey have been inserted in said groove, said collar having an internalthread to engage the thread of said socket, and means for clamping thesplit end of said socket about said collar and for clamping ksaid collarabout said shank.

9. In a propeller, a hub having a socket, a blade having a shankextending into said socket, the'inner end ortion of said shank portion fsaid socket, a connecting member mounted on said shank, held againstmovement lengthwise thereof and mounted in the outer portion of saidsocket for adjustment lengthwise thereof, and means for rigidly securingsaid connecting member in adjusted ositions in said socket and forholding said lade against rotatory movement in said socket.

10. In a propeller, ahub having a socket provided with a smoothcylindrlcal inner surface at one end thereof and having its other endsplit, a blade having a shank extending into said socket and providedwith a A part fitting within the cylindrical end portion of said socketand Aadjustable therein, said shank also having a circumferentialgroove, a connecting member fitting in said groove forrotation thereinand mounted in the outer end portion of said socket for adjustmentlengthwise thereof, and means for clamping the split end of said socketabout said connecting member and for holding said connecting member andsaid shank against relative rotatory movement.

11. In a propeller, a hub having a socket provided with a smooth clindncal inner surface at one end thereof andy having its other endsplit, a blade having a shank extending into said socket and providedwith a part fitting within the cylindrical end portion of said socketand adjustable therein, said shank also having a circumferential groove,a connecting member fitting in said groove for rotation therein andmounted in the outer end portion of said socket'for adjustmentlengthwise thereof, and means for clamping the split end of said socketabout said connectin g member and for holding said connecting member andsaid shank against relative rotatory movement.

12. In a propeller, a hubV having a socket provided with a smoothcylindrical inner surface at one end thereof and having its other endsplit, a blade having a shank extending into said socket and providedwith a part fitting. in said cylindrical end portion of said socket andadjustable therein, said shank also having a circumferential groove, asplit col-- lar fitting in said groove and mounted in the outer endportion of said socket for adjustment lengthwise thereof, and a clampingring extending about the split end of said socket.

13. In a propeller, a hub having a socket provided at one end with asmooth cylindrical inner surface and at its other end with an internalscrew thread, the threaded end of said socketr being split, a bladehaving a shank extending into said socket and provided with a partfitting in the cylindrical end portion of said socket and adjustabletherein, said shank also having a circumferential groove, a split collarfitting in said groove and having an external screw thread to engage thethread in said collar, and a clamping ring extending about the split endof said socket.

14. In a propeller, a hub having a socket, a blade having a shankextending into said socket, the inner end portion of said shank fittingsnugly but adjustably in the inner portion of said socket, a connectingmember mounted on said shank, held against movement lengthwise tFh/ereofand mounted in the outer portion of said socket for adjustmentlengthwise thereof, and means for rigidly securing said connectingmember in adjusted positions in said socket and for holding said bladeagainst rotatory movement in said socket, said socket havin an openingin the wall thereof and the shan of said blade having graduationsmovable into line with said opening.

15. In a propeller, a hub having a socket, a blade having a shank toenter said socket and having a circumferential groove, a split collarmounted in said groove and comprising two parts welded one to the otherat one side of said collar, \and means for securing said collar inadjusted positions in said socket. l

16. In a propeller, a hub having a socket,

a blade having a shank to enter lsaid socket and having acircumferential groove, a co1- lar comprising two parts adapted to beseparately inserted in said groove, the abutting edges of said parts ofsaid collar on one side of said collar having recesses to enable saidedges to be welded one to the other after said parts have been insertedin said groove, and means for securing said collar 1n adjusted positionsin said socket.

In testimony whereof, I aiix my signature hereto.

ADOLPH F. EUCI-IENHOFER.

